2j6l
Structure of aminoadipate-semialdehyde dehydrogenaseStructure of aminoadipate-semialdehyde dehydrogenase
Structural highlights
DiseaseAL7A1_HUMAN Pyridoxine-dependent epilepsy. The disease is caused by mutations affecting the gene represented in this entry. FunctionAL7A1_HUMAN Multifunctional enzyme mediating important protective effects. Metabolizes betaine aldehyde to betaine, an important cellular osmolyte and methyl donor. Protects cells from oxidative stress by metabolizing a number of lipid peroxidation-derived aldehydes. Involved in lysine catabolism.[1] [2] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedMammalian ALDH7A1 is homologous to plant ALDH7B1, an enzyme that protects against various forms of stress, such as salinity, dehydration, and osmotic stress. It is known that mutations in the human ALDH7A1 gene cause pyridoxine-dependent and folic acid-responsive seizures. Herein, we show for the first time that human ALDH7A1 protects against hyperosmotic stress by generating osmolytes and metabolizing toxic aldehydes. Human ALDH7A1 expression in Chinese hamster ovary cells attenuated osmotic stress-induced apoptosis caused by increased extracellular concentrations of sucrose or sodium chloride. Purified recombinant ALDH7A1 efficiently metabolized a number of aldehyde substrates, including the osmolyte precursor, betaine aldehyde, lipid peroxidation-derived aldehydes, and the intermediate lysine degradation product, alpha-aminoadipic semialdehyde. The crystal structure for ALDH7A1 supports the enzyme's substrate specificities. Tissue distribution studies in mice showed the highest expression of ALDH7A1 protein in liver, kidney, and brain, followed by pancreas and testes. ALDH7A1 protein was found in the cytosol, nucleus, and mitochondria, making it unique among the aldehyde dehydrogenase enzymes. Analysis of human and mouse cDNA sequences revealed mitochondrial and cytosolic transcripts that are differentially expressed in a tissue-specific manner in mice. In conclusion, ALDH7A1 is a novel aldehyde dehydrogenase expressed in multiple subcellular compartments that protects against hyperosmotic stress by generating osmolytes and metabolizing toxic aldehydes. Aldehyde dehydrogenase 7A1 (ALDH7A1) is a novel enzyme involved in cellular defense against hyperosmotic stress.,Brocker C, Lassen N, Estey T, Pappa A, Cantore M, Orlova VV, Chavakis T, Kavanagh KL, Oppermann U, Vasiliou V J Biol Chem. 2010 Jun 11;285(24):18452-63. Epub 2010 Mar 5. PMID:20207735[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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